What non-Linn sub would work with all-Linn setup?

I have a 15x15 room and am not interested in shaking the house; just supplementing the Tukans to get a better low frequency/midrange sound that is mor emusical than thudding/overwhelming. I'm concerned the Rel Stratus III and the ACI Titan II LE and the Vandy 2wq are too powerful for my humble Majik/Tukan set-up; what do you think? Should I be aiming smaller?

I don't think the Titan II LE will be "too much". It is extremely accurate, musical and subtle when required. The only way it would be too much would be if you adjusted the level to high. Otherwise you can expect a great match. This sub is known for musicality, never heard anyone say it was overpowering. Worked great with both my Concertos and now Sapphire III LEs.

HI Kirk,

I use a REL strata 3 in a 10x12 room, for 2 ch music only. It is not overpowering at all ... in fact it blends perfectly, though the room size is not able to maximize the potential of the sub. (My main speakers are Spica angelus, which are big with limited LF).

However placement was absolutely critical in such a small room ... corner sounded terrible. I ended up with the sub just in front of and to the left of the right main speaker. Since my speakers are 2.5 feet from the rear wall and I use a nearfield listening position this puts the sub next to my right foot. Looks odd, very low WAF, but sounds wonderful.

So, as long as you're prepared to live with a sub well away from the side walls I think the REL would easily integrate in your (much bigger than my) room. If it's necessary (perhaps for WAF reasons) to hide the sub away at the side of the room I think you'll have a lot more trouble.